74LVC821ADB,112 Equivalent & Substitute Parts

Part Overview

The 74LVC821ADB,112 is a D-type flip-flop logic integrated circuit manufactured by NXP USA Inc., designed for 10-bit parallel data storage and transfer applications. This component features tri-state, non-inverted outputs and operates across a 1.65V to 3.6V supply voltage range. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support, design updates, and procurement continuity.

Substiute Parts

74LVC821ADB,112

NXP USA Inc.In Stock: 96674LVC821ADB,112 Datasheet

Current PartRFQ

SN74LVC821ADBR

Texas InstrumentsIn Stock: 4538SN74LVC821ADBR Datasheet

MFR RecommendedRFQ

SN74LVC821APWR

Texas InstrumentsIn Stock: 2073SN74LVC821APWR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 74LVC821ADB,112 is determined by the following critical parameters:

Core Functional Parameters:

• D-Type flip-flop architecture with 1 element and 10 bits per element
• Tri-state, non-inverted output configuration
• Positive edge trigger mechanism
• Maximum propagation delay of 7.3 ns @ 3.3V, 50pF
• Supply voltage range of 1.65V ~ 3.6V
• Output current capability of 24 mA (high and low)
• Quiescent current of 10 µA
• Input capacitance of 5 pF

Physical and Compliance Parameters:

• Surface mount technology
• 74LVC series compatibility
• ROHS3 compliance
• MSL Level 1 rating

Substitute parts must maintain identical functional specifications and electrical characteristics. Package variations are permissible when mechanical constraints allow for board-level accommodation.

Parameter Comparison

Engineering Selection Recommendations

SN74LVC821ADBR (Texas Instruments)

This substitute maintains identical package geometry (24-SSOP) and all critical electrical parameters. The part is currently in active production status, ensuring long-term availability and supply chain stability. Clock frequency specification is reduced to 150 MHz compared to the original 200 MHz specification; however, propagation delay remains unchanged at 7.3 ns. Operating temperature range is limited to -40°C ~ 85°C versus the original -40°C ~ 125°C. ROHS3 compliance and MSL Level 1 rating are maintained. This option is recommended for applications requiring direct package compatibility without PCB redesign.

SN74LVC821APWR (Texas Instruments)

This substitute provides functional equivalence with a package variation: 24-TSSOP (0.173", 4.40mm Width) versus the original 24-SSOP (0.209", 5.30mm Width). The narrower package footprint may require PCB layout modification. All electrical parameters, including propagation delay, supply voltage range, output current, and quiescent current, remain identical. Clock frequency and operating temperature specifications match those of the SN74LVC821ADBR. Active production status and ROHS3 compliance are confirmed. This option is suitable for space-constrained applications where package miniaturization is beneficial.

Both substitute parts are manufactured by Texas Instruments and carry active product status, providing superior long-term availability compared to the obsolete NXP original.

Frequently Asked Questions (FAQ)

Q: Can the SN74LVC821ADBR directly replace the 74LVC821ADB,112 without PCB modification?

A: Yes. The SN74LVC821ADBR maintains identical package geometry (24-SSOP) and pinout. All critical electrical parameters—propagation delay, supply voltage, output current, and quiescent current—are equivalent. Direct substitution is possible without PCB redesign.

Q: What is the difference between the SN74LVC821ADBR and SN74LVC821APWR?

A: Both parts are functionally equivalent with identical electrical specifications. The primary difference is package format: SN74LVC821ADBR uses 24-SSOP (0.209" width), while SN74LVC821APWR uses 24-TSSOP (0.173" width). The TSSOP variant is narrower and requires different PCB footprint design.

Q: Why is the clock frequency specification lower on the substitute parts?

A: The substitute parts specify 150 MHz maximum clock frequency compared to the original 200 MHz. However, the maximum propagation delay remains 7.3 ns at 3.3V with 50pF load, indicating equivalent timing performance for standard applications. Verify clock frequency requirements against your specific application specifications.

Q: Are there operating temperature limitations with the substitute parts?

A: Yes. The substitute parts operate across -40°C ~ 85°C, compared to the original -40°C ~ 125°C range. If your application requires operation above 85°C, the substitute parts are not suitable. Verify your system's maximum operating temperature requirement before selection.

Q: Do the substitute parts maintain RoHS and MSL compliance?

A: Yes. Both SN74LVC821ADBR and SN74LVC821APWR are ROHS3 compliant with MSL Level 1 (Unlimited) rating, matching the original part's compliance status.

Q: Which substitute should I select for a new design?

A: For new designs, either substitute is acceptable based on package requirements. If your PCB layout accommodates standard SSOP spacing, the SN74LVC821ADBR is recommended for consistency with existing inventory. If space optimization is required, the SN74LVC821APWR offers a narrower footprint with identical electrical performance.